Scaffold hoisting mechanism



Dec. 15, 1.953 ALLENBAUGH SCAFFOLD HOISTING MECHANISM 3 Sheets-Sheet 1Filed July 1, 1949 INVENTOR. 7ia/,0/7 Awe/1b 0057/7 fifty.

Dec. 15, 1953 R. AL ENBAUGH SCAFFOLD HOISTING MECHANISM Filed July 1,1949 I5 Sheets-Sheet 2 INVENTOR. Paw/7 fl//e/M augh Dec. 15, 1953 R.ALLENBAUGH SCAFFOLD HOISTING MECHANISM 3 Sheets-Sheet 3 Filed July 1,1949 IN VEN TOR. Ba 40/? AV/e/m az/g/Y BY Hm fifty.

Patented Dec. 15,1953

UNITED STATES PATEN OFFICE one-half to Ohio Wilberd F. Feigenbaum,Mansfield,l

Application .luly 1, 1949, Serial No. 192,488

7 Claims. (01. 254-176) 1 This invention relates generally to swingstage scaffolds such as are used to support workmen and materialsadjacent the exterior of a building or wall while painting or otherwiseworking thereon. More specifically, the invention relates to apower-operated mechanism by which a swing stage scaffold is supportedand is raised and lowered as desired.

According to my invention the scaffolding is adjustably supported by twospaced single strands of rope or cable which are secured to and extenddownwardly from suitable supports which are mounted upon and projectoutwardly from the top of a building or wall. Each end of the scaffoldis suitably secured to a power-operated mechanism which in turn issupported by one of the depending ropes or cables. The two poweroperatedmechanisms are identical in construction and are adapted to be operatedindependently of each other. Their construction is such that they climbup or down the ropes or cables when the position of the scaffold isbeing changed. Normally the mechanisms are power-operated in bothdirections, either up or down, but means are provided whereby they canbe lowered by gravity if desired.

The principal object of the invention is to provide a power-operatedscaffold hoisting mechanism which is very efficient in operation andwhich is of simple construction and relatively inexpensive tomanufacture.

Another object of the invention is to provide an improved swing stagescaffold which is constructed to be adjustably supported by two spacedsingle strands of rope or cable.

Another object of the invention is to provide v in a power-operatedscaffold hoisting mechanism improved means by which the hoistingmechanism can be quickly and easily attached to or detached from asupporting cable.

Other and more limited objects of the invention will be apparent fromthe following specification and the accompanying drawings forming a partthereof wherein:

Fig. 1 is an end elevation of a swing stage scaffold having my improvedsupporting and hoisting mechanism incorporated therein;

Fig. 2 is a front elevation of one end of the scaffold shown in Fig. 1;

Fig. 3 is a rear elevation thereof;

Fig. 4 is a sectional elevation taken on the line 4-4 of Fig. 2;

Fig. 5 is a plan view of the device as shown in Figs. 1 to 4 inclusive;

Fig. 6 is an enlarged vertical section taken on the line 6-5 of Fig. 1;

Fig. 7 is an enlarged detallsectional plan view taken as indicated bythe line l---'! of Fig.6;

Fig. 8 is a detail vertical section taken on the line 8-8 of Fig. 7 and,Fig. 9 is anactual size fragmentary section taken through the hoistingdrum showing the exact contour thereof.

Referring to the drawings by reference characters the numeral Iindicates a swing stage plank which is adjustably supported for up anddown movement adjacent a wall 2 by a pair of identical units, one ofwhich is generally indicated by the numeral 3. The units 3 are eachremovably secured to a depending cable 4, each of which is secured to anelevated support and hangs down along the wall 2.

Each unit 3 comprises a main frame or casing 5 to which or within whichis mounted the entire hoisting mechanism. A stirrup 6, by which theplank I is supported is secured to the casing 5 and extends downwardlytherefrom. The stirrup B is made from round bar stock and consists of abottom horizontal section 8 anda pair of spaced side sections 9 and I0which extend upwardly therefrom into apertures in the casing 5 and areheld therein by nuts I2 and collars l3. The side 9 has an outwardlyextending semicircular section M which is adaptedto engage the wall 2 tomaintain the scaffolding a fixed distance from the wall during use. Theplank l rests upon the bottom section 8 and is clamped thereto by aclamping bar l5 and a pair of clamping nuts and bolts generallyindicated by the numeral [6. The specific construction of the' stirrupand plank clamping mechanism forms'the subject matter of my copendingapplication Serial No. 102,487, filed July 1, 1949, now Pat. No.2,639,951.

An outwardly extending bracket I! by which a guard rail 18 is supportedis secured to the casing 5 by one of the nuts [2.

A transverse shaft 20, which extends through the casing 5, is rotatablysupported by bearings 21 which are held in place by caps 22 and 23secured to the casing 5 by studs 24. A drum 25 is keyed to one end ofthe shaft 20 at 26 and is removably secured thereon by a spacer 27 andstuds 28. A hub 29, having a resilient deformable rubber tire 39vulcanized thereon, is removably secured to the other end of the shaft20 by a key 3! and a stud 32. A sprocket 33 is keyed to the shaft 29between the bearings 2| within the casing 5 as indicated at 34.

The shaft 2 0 is driven through the sprocket 33 by a chain 35 from asprocket 36 which is secured to the end of a shaft 31 which extends intothe main casing 5 from a reduction gear casing 38 suitably secured toone side of the main casing 5. The shaft 31 is driven through a standardreduction gearing within the casing 38 from a reversible motor 39secured to the opposite side of the casing 5. A brake 49 is provided toinstantly stop the rotation of thernotor armature shaft when currenttothe motor is cut off. The operation of the motor is controlled by aswitch mechanism 4| which is operated by a lever 42% As the lever 42 ismoved to cause operation of brake 40 and holds it released during theopera-, tion of the motor.

known construction which are manufactured as a single power unit byvarious manufacturers.

An idler pulley 45 is rotatably mounted, below the tire 30, on a shaft46 carried by a U-shaped bracket 4'1 which is pivotally mounted upon astud 48 extending out from one side of the casing 5. The bracket 41 isyieldingly held up in the position shown by a flat-leaf spring;49 whichis secured to the underside of the casing by one of the collars I3. Thefree end of the spring 43 engages under a pin 59; which is secured tothe bracket 41 and extends outwardly therefrom under the casing 5, andnormally holds the pin 50 up against the underside of the casing 5 whichlimits the upward movement of the bracket 41 and the pulley '45 :carriedthereby. The bracket 41 has secured thereto an arcuatearm 5| whichextends forwardly and upwardly against one side of the casing 5. Thearm;5l .is adapted to be engaged by a roller 52 which'is carried by alever 53 which is pivotally secured beside the casing 5 by the cap 23 asshown in Figs,,4 and 6. When the lever 53 is moved in a clqckwisedirection from the position sh'owngin Fig. 4 the roller 52 will engageand depress the arm 5 If which "will move the free end of the bracket 41and the pulley 45 downwardly away fro nthe, tire 3Itgfor purposes to behereinafter deseribed. The lever, 53

is normally h ld. min t e posi on, shown in. Fi

The moter educt on scar ing, and the motor controls are of standard wellthe motor 39 in either directiqn it releasesthe;

4 by a pin 55 which secures thelever 53, toa fixed substantially thesame diameterasthe diameter of the rope or cable 4. The loiverreduced,cylindrical end 69 ofthe sleeve. extends down. through an aperture '10in the .arm 56. removably secured therein by a set screw 1 I. The endofthe arm 66 is slotted as-indicatedat J2. Thewidth of the slot 12 is lessthan the diameter .of. ,the

for four or five turns. From the drum 25 the cable extends rearwardlyaround the pulley 50, and then downwardly and inwardly around the pulley6|. From the pulley 5| the cable extends forwardly over the pulley 45and under the tire 30. In order to insert the cable between the pulley45'-and the tire the pulley- 45 is first moved away from the tire 30 bythe lever 53 in the manner previously described. The cable is then movedsidewise under the tire 30 and the lever--58;-released. The spring 49then returns the pulley 45 back to normal position which tightly,grips-the cable 4 between the pulley 45 and the tire 30. From thepulley 45 the cable extends over the rear end of the bracket 41 betweenguidefingers 15 extending upwardly therefrom..and then hangs freelydownwardly.

In operation, when the drum 25 is driven in a counterclockwisedirection, as viewed in Fig. 1, the unit;3 raises itself up along therope or cable 4; and ,when the drum is driven in aclockwise directionthe unit lowers itself down the rope=or cable 4. During raising thecable 4 is wound onto the inner end of the drum25, adjacent the casing5, and is withdrawn from the outer end thereof; The tire '30 andthepulley 45 are providedto withdraw the cable from the'drum'25 duringraising, and to maintain the cable between the drum 25 and pulley 45taut at all times. The drum-25. and the tire30 are so proportioned withrespect to each other that the cable will always be Withdrawn from thedrum 25 at the same linear speed at which it is wound thereon. To insuretautness of the cable at all times the diameter of the tire-30 ispreferably such that there is a.slight slippage between the tire andcable during operation. During lowering the cable 4 is fed ontothe drumat the outerend thereof and leaves the drum at the inner end thereof.The pull'upon the cable 4 necessary to maintain it taut between the drum25: and pulley 45 is very slight, being at the most'two or three pounds.

Theshape and. size of the drum 25' may be varied, but I have found thata drum having a hard polished surface of the contour shown in Fig.19gives the. best results.

Fromthe foregoingit will be apparent to those skilled .in this artthat Ihave. provided a very simple and efficient mechanismv foraccomplishingtheobjects of my invention.

It is to: be understood that -I am not restricted tothe.specificiconstruction shown and described herein as variousmodifications may .be made thereto within the spirit ofthe invention.

What is claimed-is;-

l. Ina hoisting mechanism adaptedtomove'up and-down -a suspended-cablethe combination of a frame; a guide sleevesecured to said frame; a shaftrotatably supported by said frame below said guide-sleevey-powen meansbywhich said shaft is rotated carried by' said frame; a drum rigidlysecured to one end of said shaftja pulley rigidly secured to the-otherend ofsaid shaft; said cable being adapted-to extend downthrough saidguide sleeve and around said drum a pluralityof turnsan'd' then undersaid pulley; and means operative to hold said cable in engagement withsaid pulley.

2. 'Ina. hoisting mechanism adaptedto move up and down a suspended cablethe combinationof a frame; a guide sleevesecured' to said frame; a shaftrotatably supported by said frame below said guide sleeve; power'means""by"which"said shaft is rotated carried by said frame; a drumrigidly secured to one end of said shaft; a driving pulley rigidlysecured to the other end of said shaft; a guide pulley rotatably mountedon said frame; said cable being adapted to extend down through saidguide sleeve and around said drum a plurality of turns and then oversaid guide pulley and under said driving pulley; and means operative tohold said cable in engagement with said driving pulley.

3. A hoisting mechanism of the character described comprising asuspended cable having the upper end thereof secured to an elevatedsupporting member, a casing, a shaft rotatably mounted in said casingwith the ends thereof extending out from said casing, a drum rigidlysecured to one end of said shaft, a pulley rigidly secured to the otherend of said shaft, a driven sprocket through which said shaft is rotatedrigidly secured to said shaft between said drum and said pulley, meansoperative to drive said sprocket carried by said casing, cable guidemeans secured to said casing above said shaft, said cable extending downthrough said guide means and around said drum a plurality of turns andthen into peripheral engagement with said pulley, and means operative tomaintain said cable in engagement with said pulley during operation.

4. A hoisting mechanism of the character described comprising a,suspended cable having the upper end thereof secured to an elevatedsupporting member, a casing, a shaft rotatably mounted in said casingwith the ends thereof extending out from said casing, a drum rigidlysecured to one end of said shaft, a pulley'rigidly secured to the otherend of said shaft, a driven sprocket through which said shaft is rotatedrigidly secured to said shaft between said drum and said pulley, meansoperative to drive said sprocket carried by said casing, cable guidemeans secured to said casing above said shaft, said cable extending downthrough said guide means and around said drum a plurality of turns andthen into peripheral engagement with said pulley, means operative tomaintain said cable in engagement with said pulley during operation, andmeans by which said cable is guided from said drum into engagement withsaid pulley.

5. A hoisting mechanism of the character described comprising asuspended cable having the upper end thereof secured to an elevatedsupporting member, a casing, a shaft rotatably mounted in said casingwith the ends thereof extending out from said casing, a drum rigidlysecured to one end of said shaft, a pulley rigidly secured to the otherend of said shaft, a driven sprocket through which said shaft is rotatedrigidly secured to said shaft between said drum and said pulley, meansoperative to drive said sprocket carried by said casing, cable guidemeans secured to said casing above said shaft, said cable extending downthrough said guide means and around said drum a plurality of turns andthen into peripheral engagement with said pulley, means operative tomaintain said cable in engagement with said pulley during operation, andmeans by which said cable is guided from said drum into engagement withsaid ulley, said last mentioned means including an idler pulley mountedupon said cas- 111g.

6. A hoisting mechanism of the character described comprising asuspended cable having the upper end thereof secured to an elevatedsupporting member, a casing, a shaft rotatably mounted in said casingwith the ends thereof extending out from said casing, a drum rigidlysecured to one end of said shaft, a pulley rigidly secured to the otherend of said shaft, a driven sprocket through which said shaft is rotatedrigidly secured to said shaft between said drum and said pulley, meansoperative to drive said sprocket carried by said casing, cable guidemeans secured to said casing above said shaft, said cable extending downthrough said guide means and around said drum a plurality of turns andthen into peripheral engagement with said pulley, a bracket pivotallysecured to said casing, an idler pulley carried by said bracket inalignment with said first mentioned pulley, and resilient means biasingsaid idler pulley towards said first mentioned pulley, said idler pulleybeing operative to maintain said cable in engagement with said firstmentioned pulley during operation.

'7. A hoisting mechanism of the character described comprising asuspended cable having the upper end thereof secured to an elevatedsupporting member, a casing, a shaft rotatably mounted in said casingwith the ends thereof extending out from said casing, a drum rigidlysecured to one end of said shaft, a pulley rigidly secured to the otherend of said shaft, a driven sprocket through which said shaft is rotatedrigidly secured to said shaft between said drum and said pulley, meansoperative to drive said sprocket carried by said casing, cable guidemeans secured to said casing above said shaft, said cable extending downthrough said guide means and around said drum a plurality of turns andthen into peripheral engagement with said pulley, a bracket pivotallysecured to said casing, an idler pulley carried by said bracket inalignment with said first mentioned pulley, resilient means biasing saididler pulley towards said first mentioned pulley, said idler pulleybeing operative to maintain said cable in engagement with said firstmentioned pulley during operation, and means including a manuallyoperable pivoted lever operative to move said idler pulley away fromsaid first mentioned pulley to release said cable from said firstmentioned pulley.

RALPH ALLENBAUGH.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 344,306 Chambers June 22, 1886 1,328,500 Donaldson Jan. 20,1920 1,685,015 Aycock Sept. 18, 1928 2,508,187 Niemlec May 16, 1950FOREIGN PATENTS Number Country Date 5,906 Great Britain Apr. 6, 1891306,689 Italy Mar. 29, 1933

